Things that make you.....lean

[DCIV]

List the things that have a direct and huge impact on running lean. Like puttering and hardly any power till higher RPM’s lean.

Ready go.


Coop

[mjannusch]

Bad O2 sensor
Low fuel pressure
Incorrect ecu calibration for injector size
Bad MAF sensor
Unmetered air entering intake side (open atmosphere bov stuck open, etc.)

[vr4]

Misfire

[DCIV]

[quote=""vr4""]Misfire[/quote]

I would think this would be rich....I had on my addenda to change out the plugs as they were old and not gapped correctly. But is this really correct?


Coop

[DCIV]

[quote=""mjannusch""]Bad O2 sensor
Low fuel pressure
Incorrect ecu calibration for injector size
Bad MAF sensor
Unmetered air entering intake side (open atmosphere bov stuck open, etc.)[/quote]

I thought bad o2 caused rich conditions? I need to see if my maft settings got moved somehow.


Coop

[vr4]

Bad o2 can cause rich or lean.

Misfires will show up as lean on a scanner. Oxygen sensors measure oxygen content. Misfire means excessive oxygen in exhaust. This would indicate lean to the computer causing it to add more fuel.

[DCIV]

O2’s are reading. Is there any difference between reading and reading correctly?

So say my coils are fairly uniform I am going to say this isn’t my issue.

Any other suggestions?

This really pisses me off. I’ve torn apart and put back together more times than I can count and always get it to run. Always figure out all issues. Read just about every thread on 3si. And I am so stumped it’s annoying.


Coop


Coop

[mjannusch]

Mod list?

[DCIV]

Oh jebus. I will try.

Evo 550 injectors
Flashed ecu
Oohnoo dual feed
Supra Hotwire pump
FMIC
Maft
Upgrades clutch
Bell house brace
Ss tcass
16g’s and adapter plates

As far as fresh stuff as well, rebuilt TB 2 years ago, new fuel filter last year.

Coop

[mjannusch]

ECU flashed with what? What are the MAFT settings? Are you sure this isn't just a tuning problem?

[DCIV]

[quote=""mjannusch""]ECU flashed with what? What are the MAFT settings? Are you sure this isn't just a tuning problem?[/quote]

I’m not sure if anything. I am worried about changing my pins on the harness to make read the o2’s I might have fucked something up.

I have flashed chrome v2 on it.

I will get my maft settings as it could be something. I did remove my center console to instal the shifter base, maybe something got flipped.


Coop

[aaronatstate]

Uneven floors....

[quote=""DCIV""]I’m not sure if anything. I am worried about changing my pins on the harness to make read the o2’s I might have fucked something up.

I have flashed chrome v2 on it.

I will get my maft settings as it could be something. I did remove my center console to instal the shifter base, maybe something got flipped.


Coop[/quote]

Is Chrome set up with the proper injector sizes and latencies? That is a must. Also what do you have the Mass Air Setting set at in Chrome?

Also, do you have a aftermarket fuel pressure regulator? If so, what is it set at?

[DCIV]

[quote=""aaronatstate""]Uneven floors....



Is Chrome set up with the proper injector sizes and latencies? That is a must. Also what do you have the Mass Air Setting set at in Chrome?

Also, do you have a aftermarket fuel pressure regulator? If so, what is it set at?[/quote]

So I haven’t touched my chrome tune in 3 years since it ran fine. It was set up for proper stuff then, I asked Jeff if a reflash might fix this, he didn’t think so but at this point it can’t hurt.

My FPR is reading 37 with a vac line hooked up.

Finally got this baby to sleep so I will go look at my maft settings.


Coop

[DCIV]

Aux is set to 6

Dip switches the first is up, rest are down

Then the roll dials I’m on 4,0,0,D


Coop

[DCIV]

http://www.3si.org/forum/f35/what-am-i- ... -a-762930/

Hmmmmm. Maybe my maft is wrong.


Coop

[Chris GTO TT]

[quote=""aaronatstate""]Uneven floors....
[/quote]

Oh good I wasn't the only one thinking that...

[DCIV]

Going off this chart http://www.fullthrottletech.com/attachm ... hmentid=72

I changed a couple things.

I’m now on aux 8

Same dip switches.

Moved to 2,0,0,B

Idle moved to where it should. Let’s go for a test drive.


Coop

[DCIV]

Okay. So that was driveable. I took it about 2 miles before coming home. Still running lean, still bogging and running rich.

At 2,000rpm and 20mph I should have zero issue in 2nd gear. But I did. It would even pop out my tail pipe. But man you get hire and it’s a rocket ship.

So odd.

Does the ecu need to have the battery cut off so it can redo some maps or something?


Coop

[DCIV]

I think by me going 2,0,0,b I was actually saying 360 injectors for idle and then 340 for mid and upper. Maybe that’s why I was lugging.

I don’t know how this thing ran before.


Coop

[DCIV]

So others have said 0 for the middle and high. I believe them, but why am I having issues at 2k?

Like I said, that was driveable. I could drive that but it’s not right, or even as good as it was.

Does the 99 ecu’s with their learn function, could they have learned something from running wrong or set to the wrong injector off of the maft?


Coop